351 research outputs found

    Identification of a Chitin-Binding Protein Secreted by Pseudomonas aeruginosa

    Get PDF
    One of the major proteins secreted by Pseudomonas aeruginosa is a 43-kDa protein, which is cleaved by elastase into smaller fragments, including a 30-kDa and a 23-kDa fragment. The N-terminal 23-kDa fragment was previously suggested as corresponding to a staphylolytic protease and was designated LasD (S. Park and D. R. Galloway, Mol. Microbiol. 16:263-270, 1995). However, the sequence of the gene encoding this 43-kDa protein revealed that the N-terminal half of the protein is homologous to the chitin-binding proteins CHB1 of Streptomyces olivaceoviridis and CBP21 of Serratia marcescens and to the cellulose-binding protein p40 of Streptomyces halstedii. Furthermore, a short C-terminal fragment shows homology to a part of chitinase A of Vibrio harveyi. The full-length 43-kDa protein could bind chitin and was thereby protected against the proteolytic activity of elastase, whereas the degradation products did not bind chitin. The purified 43-kDa chitin-binding protein had no staphylolytic activity, and comparison of the enzymatic activities in the extracellular medium of a wild-type strain and a chitin-binding protein-deficient mutant indicated that the 43-kDa protein supports neither chitinolytic nor staphylolytic activity. We conclude that the 43-kDa protein, which was found to be produced by many clinical isolates of P. aeruginosa, is a chitin-binding protein, and we propose to name it CbpD (chitin-binding protein D)

    Challenging the production function approach to assess the developmental effects of FDI

    Get PDF
    From a theoretical point of view, it is traditionally assumed that foreign firms possess a centrally accumulated firm-specific technological advantage over domestic firms (see, for example, Findlay, 1978; Dunning, 1979). Given a sufficient level of absorptive capacity and human capital, domestic firms in host economies are able to benefit from various externalities stimulated by the presence of foreign firms

    Pharmacological Investigation of Protein Kinase C- and cGMP-Dependent Ion Channels in Cultured Olfactory Receptor Neurons of the Hawkmoth Manduca sexta

    Get PDF
    In the hawkmoth Manduca sexta, pheromone stimuli of different strength and duration rise the intracellular Ca2+ concentration in olfactory receptor neurons (ORNs). While second-long pheromone stimuli activate protein kinase C (PKC), which apparently underlies processes of short-term adaptation, minute-long pheromone stimuli elevate cyclic guanosine monophosphate (cGMP) concentrations, which correlates with time courses of long-term adaptation. To identify ion channels involved in the sliding adjustment of olfactory sensitivity, inside-out patch clamp recordings on cultured ORNs of M. sexta were performed to characterize Ca2+-, PKC-, and cGMP-dependent ion channels. Stepping to positive holding potentials in high intracellular Ca2+ elicits different Ca2+-dependent ion channels, namely small-conductance channels (2–20 ps), medium-conductance channels (20–100 ps), and large-conductance channels (>100 ps). Ion channels of 40, 60, and 70 ps opened after PKC activation, whereas 10- and >100-ps channels were observed less frequently. Application of 8-bromo cyclic guanosine monophosphate opened 55- and 70-ps channels and increased the open probability of >100-ps channels, whereas even in the presence of phorbol ester 40-ps channels were inhibited. Thus, cGMP elevations activate a different set of ion channels as compared with PKC and suppress at least one PKC-dependent ion channel

    The WISDOM of power spectra: how the galactic gravitational potential impacts a galaxy?s central gas reservoir in simulations and observations

    Get PDF
    Observations indicate that the central gas discs are smoother in early-type galaxies than their late-type counterparts, while recent simulations predict that the dynamical suppression of star formation in spheroid-dominated galaxies is preceded by the suppression of fragmentation of their interstellar media. The mass surface density power spectrum is a powerful tool to constrain the degree of structure within a gas reservoir. Specifically here, we focus on the power spectrum slope and aim to constrain whether the shear induced by a dominant spheroidal potential can induce sufficient turbulence to suppress fragmentation, resulting in the smooth central gas discs observed. We compute surface density power spectra for the nuclear gas reservoirs of fourteen simulated isolated galaxies and twelve galaxies observed as part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM) project. Both simulated and observed galaxies range from disc-dominated galaxies to spheroids, with central stellar mass surface densities, a measure of bulge dominance, varying by more than an order of magnitude. For the simulations, the power spectra steepen with increasing central stellar mass surface density, thereby clearly linking the suppression of fragmentation to the shear-driven turbulence induced by the spheroid. The WISDOM observations show a different (but potentially consistent) picture: while there is no correlation between the power spectrum slopes and the central stellar mass surface densities, the slopes scatter around a value of 2.6. This is similar to the behaviour of the slopes of the simulated galaxies with high central stellar mass surface densities, and could indicate that high shear eventually drives incompressible turbulence

    Establishment of a New Cell Line from Lepidopteran Epidermis and Hormonal Regulation on the Genes

    Get PDF
    When an insect molts, old cuticle on the outside of the integument is shed by apolysis and a new cuticle is formed under the old one. This process is completed by the epidermal cells which are controlled by 20-hydroxyecdysone (20E) and juvenile hormone. To understand the molecular mechanisms of integument remolding and hormonal regulation on the gene expression, an epidermal cell line from the 5th instar larval integument of Helicoverpa armigera was established and named HaEpi. The cell line has been cultured continuously for 82 passages beginning on June 30, 2005 until now. Cell doubling time was 64 h. The chromosomes were granular and the chromosome mode was from 70 to 76. Collagenase I was used to detach the cells from the flask bottom. Non-self pathogen AcMNPV induced the cells to apoptosis. The cell line was proved to be an epidermal cell line based on its unique gene expression pattern. It responded to 20E and the non-steroidal ecdysone agonist RH-2485. Its gene expression could be knocked down using RNA interference. Various genes in the cell line were investigated based on their response to 20E. This new cell line represents a platform for investigating the 20E signaling transduction pathway, the immune response mechanism in lepidopteran epidermis and interactions of the genes

    Allogeneic Stem Cell Transplantation for Myelodysplastic Syndrome Patients with a 5q Deletion

    Get PDF
    The deletion (5q) karyotype (del [5q]) in patients with myelodysplastic syndrome (MDS) is the most common karyotypic abnormality in de novo MDS. An increased number of blasts and additional karyotypic abnormalities (del [al]+) are associated with a poor outcome. We analyzed the outcome of allogeneic hematopoietic cell transplants (HCT) in patients suffering from MDS with only del (5q) or del (5q)+. A total of 162 patients, of median age 54 years (range, 9 to 73), having MDS and del (5q) abnormalities received HCT from identical siblings (n = 87) or unrelated donors (n = 75). The cumulative incidence of nonrelapse mortality and relapse incidence at 4 years was 29% (95% CI, 22 to 36) and 46% (95% CI, 38 to 54), whereas the estimated 4 year survival, relapse-free and overall, was 25% (95% CI, 18 to 33) and 30% (95% CI, 23 to 38), respectively. In a multivariate analysis patients with del (5q) and a blast excess displayed poorer survival (hazard ratio, 2.38; 95% CI, 1.44 to 3.93; PPeer reviewe

    Real-world evidence in Alzheimer’s disease: the ROADMAP Data Cube

    Get PDF
    INTRODUCTION:The ROADMAP project aimed to provide an integrated overview of European real-world data on Alzheimer's disease (AD) across the disease spectrum. METHODS:Metadata were identified from data sources in catalogs of European AD projects. Priority outcomes for different stakeholders were identified through systematic literature review, patient and public consultations, and stakeholder surveys. RESULTS:Information about 66 data sources and 13 outcome domains were integrated into a Data Cube. Gap analysis identified cognitive ability, functional ability/independence, behavioral/neuropsychiatric symptoms, treatment, comorbidities, and mortality as the outcomes collected most. Data were most lacking in caregiver-related outcomes. In general, electronic health records covered a broader, less detailed data spectrum than research cohorts. DISCUSSION:This integrated real-world AD data overview provides an intuitive visual model that facilitates initial assessment and identification of gaps in relevant outcomes data to inform future prospective data collection and matching of data sources and outcomes against research protocols
    corecore